


Quickie

by doyouwanttohaveabadtime



Category: Undertale (Video Game)
Genre: Other, Quickie, tentadick
Language: English
Status: Completed
Published: 2015-12-06
Updated: 2015-12-06
Packaged: 2018-05-05 08:49:14
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 402
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5369159
Author URL: https://archiveofourown.org/users/doyouwanttohaveabadtime/pseuds/doyouwanttohaveabadtime
Summary: <blockquote class="userstuff">
              <p>You always know what he wants, even if he’s too shy to ask.</p>
            </blockquote>





	Quickie

**Author's Note:**

> Another drabble that kind of got out of hand. I have ideas for longer fics but have been busy with school! Hopefully once things level out I can actually write something longer again ;u; Reader is of ambiguous gender with ambiguous genitalia! Originally posted at my tumblr; doyouwanttohaveabadtime.tumblr.com.

You can tell he’s attempting to stay professional, but as you slide your tongue up his slick tentacle, he makes a very lewd, pleasured noise and rolls his hips up. Without warning, you swallow him, humming softly as you pump what you can’t fit in your mouth with your hand. There’s sticky black fluid all over your lips, and some of it starts to drip past your chin. Gaster shudders and gently lifts your face up. You pull off of the tentacle with a pop and wipe the drool from your mouth, and you can’t quite hide the smirk on your face. You know what he wants, even if he’s too shy to ask. 

You mount him as quick as you can, positioning yourself. You tease your entrance slowly, pumping two fingers inside, giving him a show. You prepared yourself ahead of time so you spread yourself easily. The tentacle lazily strokes against your palm and you grasp it gently before finally lowering yourself onto it. It’s thick, and as it presses into you, you can feel it writhe and squirm inside your body, rubbing against your sensitive walls. Gaster’s fingers dig into your hips as you move, slowly at first as to not hurt yourself. Soon though, you’re riding him like a pro, gasping every time the widest part of the tendril stretches you open. 

“Y-you’re so big!” you exclaim, grinning as you peer up at Gaster’s flushed face. “It f-feels s-so good!” You know he loves it when you’re vocal. “Please, fill me up,” you pant, gripping his shoulders for leverage as you move faster. “I want your cum i-inside of me!” The tentacle twitches and pulses and with a grunt, Gaster releases in you, warm and sticky. You bury your head in his chest, muffling your moans of pleasure as you reach your own orgasm as well, clenching tight around him. 

Your body’s limp as Gaster lifts you off of him, and the tentacle slides out of you with a wet plop. Cum drips from your entrance onto his slacks, making a damp spot. You shimmy your way up and kiss his cheek before nuzzling your head into the crook of his neck. “That was pretty quick,” you say, yawning loudly. He wraps his arms around your torso. “We were both pretty into it today, huh?” you chuckle. “Guess that just means we’ll have to try it again, right?”


End file.
